#define _CRT_SECURE_NO_WARNINGS 1
#pragma once
#include<iostream>
#include<string>
#include<assert.h>
using namespace std;
namespace K
{
	class string
	{
	public:
		typedef char* iterator;
		typedef const char* const_iterator;
		iterator begin()
		{
			return _str;
		}
		iterator end()
		{
			return _str + _size;
		}
		const_iterator begin() const
		{
			return _str;
		}
		const_iterator end() const
		{
			return _str + _size;
		}
		//string()
			//:_str(new char[1]{'\0'})
			//,_size(0)
			//,_capacity(0)
		//{ }
		string(const char* str="")
		{
			_size = strlen(str);
			_capacity = _size;
			_str = new char[_capacity + 1];
			strcpy(_str, str);
		}
		~string()
		{
			delete[] _str;
			_str = nullptr;
			_size = _capacity = 0;
		}
		const char* c_str() const
		{
			return _str;
		}
		size_t size() const
		{
			return _size;
		}
		size_t capacity() const
		{
			return _capacity;
		}
		char& operator[](size_t pos)
		{
			assert(pos < _size);
			return _str[pos];
		}
		const char& operator[](size_t pos) const
		{
			assert(pos < _size);
			return _str[pos];
		}
		void reserve(size_t n);
		void push_back(char ch);
		void append(const char* str);
		string& operator+=(char ch);
		string& operator+=(const char* str);
		void insert(size_t pos, char ch);
		void insert(size_t pos, const char* str);
		void erase(size_t pos, size_t len=npos);
	private:
		char* _str;
		size_t _size;
		size_t _capacity;
		//static const size_t npos=-1;
		static const size_t npos;
		//static const int N = 10;
		//int buffer[N];
	};
	void test_string1();
	void test_string2();
}
